TORONTO — The old-school Eugenie Bouchard returned to the court Thursday at the Rogers Cup.

Her smile was back and there was spring in her step. She looked like the player who enjoyed a breakout season in 2014.

The only thing missing was a victory.

Bouchard, who has been unable to shake a long singles slump, teamed with Karolina Pliskova for a rollicking doubles match at the Aviva Centre's grandstand court. They pushed Germany's Anna-Lena Groenefeld and Kveta Peschke of the Czech Republic to the brink before dropping a 7-5, 1-6, 11-9 decision.

The result didn't seem to bother the Canadian or her partner in the slightest.

Bouchard was clearly having fun playing a loose, carefree style while Pliskova — the world No. 1 in singles — joined her for the ride.

"I think that's something maybe I can try to use in my singles, just put less pressure on myself," Bouchard said. "It's more fun to play that way as well."

Pliskova had defeated Japanese qualifier Naomi Osaka 6-2, 6-7 (4), 1-0 a few hours earlier to lock up a spot in the singles quarter-finals. Osaka was forced to retire due to an abdominal injury.

The Czech star will next play sixth-seeded Caroline Wozniacki of Denmark, who defeated 10th-seeded Agnieszka Radwanska of Poland 6-3, 6-1.

Second-seeded Simona Halep of Romania needed only 59 minutes to breeze by Barbora Strycova of the Czech Republic 6-1, 6-0 while American Sloane Stephens upset third-seeded German Angelique Kerber 6-2, 6-2.

Caroline Garcia of France advanced with a 6-4, 6-2 win over American Catherine Bellis and Lucie Safarova of the Czech Republic moved on with a 6-3, 6-7 (3), 6-2 victory over Ekaterina Makarova of Russia.

With little time to form an on-court rapport, Bouchard and Pliskova relied on their instincts against their eighth-seeded opponents.

The six-foot-one Pliskova has an imposing serve and the ground strokes to match. Bouchard, from Westmount, Que., picked her spots effectively with strong net play and several winners from the backcourt.

Bouchard and Pliskova appeared set to advance to the quarter-finals, but Groenefeld and Peschke fought off three match points in the tiebreak before nailing down the win.

Bouchard reached the No. 5 spot in the world singles rankings in 2014 but she currently holds the No. 70 position. The latest first-round loss came to Donna Vekic of Croatia earlier this week.

Her singles matches have been marked by frequent looks of exasperation and the occasional racket smash. She's not afraid to show her frustration.

Bouchard was like a free spirit on the doubles court though, appearing energized and fresh. It looked as if she had rediscovered her love for the sport.

"That's how I like to play doubles," she said. "I mean I'm obviously a singles player but I think playing doubles once in a while can help my game.

"But also going out, swinging, being relaxed — that's how (Pliskova) likes to play as well — so we were on the same page."

Bouchard has played doubles at four other events this season and used a different partner each time. Pliskova sent her a text to see if she'd like to team up this week and the Canadian jumped at the opportunity.

"I think for her it's definitely a good choice that she's started to play doubles a little bit," Pliskova said. "Because if you win a few matches then you can still get the confidence back from doubles. In singles, it's tough ... I think it's just in the head. I think overall she's playing well."

Later Thursday, fifth-seeded Ukrainian Elina Svitolina defeated American Venus Williams 6-2, 6-1 and Spain's Garbine Muguruza dispatched Australian qualifier. Ashleigh Barty 6-0, 3-6, 6-2.

In doubles play, Ottawa's Gabriela Dabrowski and Latvia's Jelena Ostapenko defeated Germany's Julia Goerges and Ukraine's Olga Savchuk 4-6, 6-2, 10-3. The top-seeded doubles team of Makarova and Russia's Elena Vesnina beat Bianca Andreescu of Mississauga, Ont., and Montreal-based Carson Branstine 6-1, 6-1.

Play continues at the US$2.74-million tournament through Sunday.

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